With a floor cleaning appliance of the aforementioned kind it is possible to autonomously clean a floor surface, for example, by sweeping and/or by vacuuming. For sensing obstacles at or on the floor surface, the floor cleaning appliance comprises the sensing part, which is connected to the displaceable holding part and is held on the floor cleaning appliance by means of the holding part. For example, the holding part, as well as the undercarriage, is held on a chassis of the floor cleaning appliance. When the sensing part contacts an obstacle, the holding part can be displaced and the detection element actuated. A signal relating thereto is provided for acting on the drive device, for example, is transmitted to a control device of the floor cleaning appliance, which, in turn, is in operative connection with the drive device. When the floor cleaning appliance senses an obstacle, the state of movement of the floor cleaning appliance can be changed, for example, the floor cleaning appliance can be stopped, or a change in the direction of travel takes place.
EP 0 274 310 B1 describes a floor cleaning appliance. Upon sensing an obstacle head-on, the holding part of the floor cleaning appliance is displaced and actuates a detection element, whereupon the floor cleaning appliance is stopped. In the event of an off-center collision with an obstacle at the side, the holding part is rotated about an axis of rotation aligned perpendicularly to the direction of displacement. The detection element can be actuated by additional displacement of the holding part. Particularly since the holding part has a considerable size and, therefore, a high inertia, it may happen that the rotation is not followed by displacement of the holding part, and the floor cleaning appliance maintains its direction of travel in spite of the collision with an obstacle, which may result in damage to the floor cleaning appliance.
A floor cleaning appliance with a rotatable and displaceable sensing part is also described in WO 02/071175 A1.
DE 24 48 156 describes a further floor cleaning appliance with a pivotable sensing part.
An object underlying the present invention is to provide a generic floor cleaning appliance, with which collisions with obstacles can be detected more reliably.